Array Wierdness

[Steven Schveighoffer]

On 8/10/22 11:26 AM, Ruby The Roobster wrote:
> On Wednesday, 10 August 2022 at 15:19:41 UTC, Ruby The Roobster wrote:
>> Take the following code:
>>
>> ```d
>> void main()
>> {
>>     shared class C { bool opEquals(const(shared(C)) rhs) const shared  
>> { return true;}}
>>     const(C) c = new C();
>>     const(C)[] a = [c];
>>     const(C)[] b = [c];
>>     assert(a[0] == b[0]);
>> }
>> ```
>>
>> This code (supposedly) checks whether ```a``` and ```b``` are equal.  
>> The thing is, it doesn't, because C is defined as ```shared```.  Is 
>> there anything I can do to fix this?
> 
> Wait, is this a regression?
> 
> --------------------------------------------------------------------------------------- 
> 
> 
> Up to      2.098.1: Success and no output
> Since      2.099.1: Failure with output:
>      -----
>      onlineapp.d(7): Error: none of the overloads of template 
> `object.opEquals` are callable using argument types 
> `!()(shared(const(C)), shared(const(C)))`
> /path/to/dmd.linux/dmd2/linux/bin64/../../src/druntime/import/object.d(269):        
> Candidate is: `opEquals(LHS, RHS)(LHS lhs, RHS rhs)`
>        with `LHS = shared(const(C)),
>             RHS = shared(const(C))`
>        must satisfy the following constraint:
>      `       is(LHS : const(Object))`
>      -----

Yes. It's a druntime regression.

In the compiler, instances shared classes are now treated as if the 
variables were declared `shared`. Prior to this, they were just `C`. 
Druntime was not updated to reflect this.

A related bug: https://issues.dlang.org/show_bug.cgi?id=23140

-Steve